The invention relates generally to epoxydecenal compounds, and specifically to isomeric forms of epoxydecenal having enhanced flavor potency.
Epoxydecenal (trans-4,5-epoxy-(E)-2-decenal) (C10H16O2, MW 168.24) is a known flavorant for foods, beverages, or other products. It enhances the flavor and/or odor of these products, making the products more desirable to the consumer. Epoxydecenal is formed from the degradation of fats, and is found in many foodstuffs, including both foods and beverages such as barley malt, French fries, olive oil, baguettes, peanut oil, hazelnut oil, pumpkinseed oil, rambutan fruit, puff pastries, wheat bread, cooked chicken, cooked beef, cooked pork, boiled salmon, cod, anchovy, oat meal, butter, buttermilk, French beans, oranges, and others.
The synthesis of epoxydecenal has been described. The compound was prepared by homologation of the precursor aldehyde epoxide using a Wittig reaction. Epoxydecenal exists in nature as a mixture of isomers. The epoxide may be in the cis or trans configuration. For the trans epoxide there are two possible isomers, the (S,S) isomer (FIG. 1A) and the (R,R) isomer (FIG. 1 B). The absolute configuration of these two isomers will be either (+) or (xe2x88x92) which is determined by the optical rotation. The substantially pure (S,S) isomer of epoxydecenal has been synthesized, as reported by Zamboni et al., as an intermediate in the total synthesis of 14S,15S-oxido 5Z,8Z, 10E, 12E-eicosatetraenoic acid (Tetrahedron Letters, 24:4899-4902 (1983)). The absolute configuration was deduced from a precursor of 2-deoxy-D-ribose.
The use of a catalyst to yield enantiomerically enriched mixtures of epoxydecenal has been reported by Jacobsen et al. (Chang, Lee, and Jacobsen, J. Org. Chem., 58:6939-6941 (1993)). The report demonstrated the utility of this catalyst to perform regio- and enantioselective catalytic epoxidations, in which conjugated polyenes-cis alkenes are reacted in favor of trans alkenes. The catalytic reaction results in mainly the trans epoxide and yields a high enantiomeric enrichment. An enantiomerically enriched mixture of trans-4,5-epoxy-(E)-2-decenal was synthesized from the cis, trans-decadienol, with an enantiomeric excess (EE) of 83%. There was no mention or suggestion by Jacobsen et al. for using this compound as a flavor or ingredient, and the odor of the individual isomers ((xe2x88x92), (+) ) was not described.
Racemic mixtures of epoxydecenal have been synthesized for use as an odorant (Schieberle et al,. Z Lebensm Unters Forsch 192:130-135 (1991)and Lin et al., Lipids (1999), 34:1117-1126). In Schieberle, epoxidation of decadienal with 3-chloroperbenzoic acid yielded the epoxydecenal mixtures. The compound was prepared for evaluation as an odorant in wheat bread crumbs and for comparison of gas chromatography retention times with known samples. Lin synthesized epoxydecenal using a Wittig reaction as a key step. In both of these reports, there is no mention of the odor activity of the individual optical isomers. The odor of the geometric isomers (cis and trans) was described by Schieberle (Book of Abstracts, 218th American Chemical Society National Meeting, New Orleans, August 22-26 (1999), AGFD-016).
Among all the reports describing the use of epoxydecenal in foodstuffs, the publication by Buttery (J. Agric. Food Chem., 46:2764-2769 (1998)), studying corn tortilla chips, mentioned the use of epoxydecenal isomers and stated that two isomers of 4,5-epoxy-(E)-2-decenal (labeled as isomer A and isomer B) were identified. Buttery neither teaches nor discloses the odor or potency of the individual isomers.
A method to enhance intensity of an epoxydecenal flavorant taking advantage of activity of epoxydecenal isomers is desirable.
The invention is directed to an epoxydecenal flavorant composition having increased potency. The composition contains epoxydecenal that has been enriched to contain at least about 90% of the (xe2x88x92) isomeric form. In some embodiments, the composition may contain up to about 99% of the (xe2x88x92) isomeric form. The composition may be used to flavor foodstuffs, such as foods and beverages, or it may be used in other products such as health care products and pharmaceuticals. It may be added as a neat compound, in a solvent, in a solid form, or in an encapsulated form.
The invention is also directed to a method of flavoring a product with epoxydecenal (trans-4,5-epoxy-(E)-2-decenal). In the method, epoxydecenal (trans-4,5-epoxy-(E)-2-decenal) that has been enriched to contain at least about 90% of the (xe2x88x92) isomeric form is added in an amount sufficient to flavor the product. The amount may be in the range of 0.001 ppb to 100 ppm. The product may be a foodstuff.
The composition provides an epoxydecenal (trans-4,5-epoxy-(E)-2-decenal) flavorant with enhanced intensity, permitting a lower concentration of the flavorant to achieve a desired product taste and/or aroma. This results in a more efficient and economical product. These and other embodiments and advantages of the invention will be apparent in light of the following figures and detailed description.